DauntlessOBD User Guide

OBD2 Communications Interface for Mobile Apps and Computers

Cautions and Disclaimers

For dry use only; do not expose to moisture. For use in US-market automobiles with standard 12 Volt DC power, that that implement OBD-II via the CAN protocol.

Ensure that the placement of this device and any wiring extensions cannot interfere with the movement or operation of the steering wheel, steering column, foot pedals, or other controls. Use care to avoid bumping into the device when plugged in, especially when entering or exiting the vehicle.

While this product can be useful in reading trouble codes, test results, and sensor values to diagnose problems on a vehicle, it is not all-inclusive or definitive. This product does not replace a mechanic. You should consult a properly qualified automotive technician for interpretation, verification, and advice before taking any action. Clearing trouble codes will typically not fix anything, and often will erase diagnostic data that would be useful to an automotive technician or repair shop.

Features, availability, and compatibility are subject to change without notice.

Data streams, performance, and other features and capabilities will vary depending on vehicle and app / software, and may change in future updates.

Dauntless Devices LLC, and its affiliates and distributors, are not liable for how you or third party apps use this product.

We do not claim any endorsement by, or affiliation with, ELM Electronics, SavvyCAN, GVRET, or any other product or manufacturer, unless explicitly stated. All trademarks are property of their respective owners, and are referenced to provide compatibility information.

DauntlessOBD, Dauntless Devices, and associated logos are trademarks of Dauntless Devices LLC. This product and its documentation are Copyright © 2023 Dauntless Devices LLC. All Rights Reserved.

Supported Vehicles

This product plugs into the vehicle’s OBD-II port and requires a vehicle that implements OBD-II using the CAN protocol.

This covers all 2009 and newer US-market gasoline and diesel cars, pickup trucks, and SUVs, along with certain others dating back as far as 2004. Click here for details.

100% Electric Vehicles are typically not be expected to work properly with this product, even if equipped with an OBD port. Hybrid gasoline/electric vehicles conforming to the OBD-II standard are expected to work.

This product does not support older OBD-II protocols such as J1850 VPW / PWM, ISO-9141, or ISO-14230 / KWP “K-Line”. J1939 protocol is not supported.

Supported Apps

In addition to the official Dauntless OBD app, this device is also compatible with the ELM327 protocol, accessible via Low Energy (LE) wireless (iOS and Android) or USB wired (computers).

Known compatible apps and specific tips for them are listed here: DauntlessOBD App Compatibility

For compatible smartphone apps, you must have first paired this device to your phone. Then you will typically need to go into the app’s settings to select “LE” or similar communications mode, and may also need to select “ELM327” mode and/or your specific DauntlessOBD device.

Please ensure that your desired app supports ELM327 devices over LE wireless, or contact your app’s developer to ask them to add it. We openly offer developer information for app developers who wish to add DauntlessOBD support.

Device Buttons

  • Rear Button: This is the user button to control wireless pairing. See the “Wireless Communications” section for more info.

Device Lights

Please note that we’ve intentionally softened these lights so that this product doesn’t light up your floorboard like Las Vegas at night, as some other OBD dongles do. As such, these lights may be less apparent when viewed in daylight, but a glow should be visible if you are trying to see it under the dash.

  • Green Light (left): Status / Activity Indicator. Will flash periodically when idle, only every 30 seconds when in sleep mode, or quickly / irregularly when in use for communications. Will have a quick regular flash when in wireless pairing mode. May also blink out a two digit code (long/short pattern) in the event of an error.
  • Red Light (right): Power Indicator. This will always be illuminated when the device has power available to it, even if there are no communications. Being that this is typically on all the time, we’ve made this somewhat dimmer than the green light, so only a faint red glow may be visible in daylight.

Wireless Communications

  • DauntlessOBD supports Low-Energy wireless communications for compatible Android and iOS mobile devices.
  • For your security, the DauntlessOBD device will not accept wireless commands until it has been paired with your mobile device, and this pairing process requires you to physically press the button on the product.
  • Using the official DauntlessOBD app is the easiest way to pair with your mobile device, and then this device can also be used by other compatible apps that you have installed.

If you wish to instead pair it manually, please use the following steps:

  1. First, hold the rear button for 3+ seconds until the green status light starts flashing quickly. This enables pairing mode for approximately 1 minute. Although this product will be visible in wireless scans, it will not accept a new pairing unless this pairing mode is active.
  2. Android: Open the system Settings app, go to Connected Devices, select Pair New Device, select the DauntlessOBD_xxxxxx device from the list, then accept any pairing prompts that appear. Note that the menu layout and naming can vary between devices and versions of Android. You might also get two pairing prompts and need to accept both of them. In some cases, the pairing prompt(s) might only be subtly indicated in the top bar and would require swiping down on it to access. For these reasons and more, you’ll likely have a better user experience using the official DauntlessOBD app to streamline this process for you.
  3. iOS: Open a compatible app and have it attempt to connect to this product. A system pairing prompt should then be displayed. Accept any pairing prompts that appear.

If pairing fails, please make sure that pairing mode is still active (green status light flashing quickly), and that your mobile device is in close proximity to this product. If problems persist, restart your mobile device, unplug this product, then plug it back in and try the pairing process again.

To clear all previously paired devices, hold the rear button down for 10+ seconds. You should observe the green status light start to flash quickly after 3+ seconds (pairing mode), and then return to a normal periodic flash after you’ve held it down continuously for 10+ seconds and the pairings have been cleared.

Wired Communications

The DauntlessOBD device also offers a USB-C style port that can be used to connect it directly to your computer, or with certain Android devices and apps (support varies). It should appear on computers as a serial port (aka COM port). This option is useful for faster and more reliable communications than wireless, especially when using CAN monitoring / sniffing tools.

Troubleshooting & Known Issues

Troubleshooting Wireless Communications Issues

  • Your mobile device must be compatible with BT 4.2 or newer at a minimum, with 5 or newer being recommended for best results. Wireless compatibility and performance may vary depending on the mobile device, its operating system, and actual signal conditions.
  • For your security, this device must be paired to your mobile device using a physical button press, before any apps will be able to successfully communicate with it wirelessly. This typically should only need to be done once per mobile device. For best results, use the official DauntlessOBD app to guide you through first time device setup and establish the wireless pairing for all supported apps to use.
  • Disconnect the charging cable from your mobile device. Some mobile devices have been observed to have more trouble establishing this type of wireless connection while being charged. Once the connection is established, charging may be resumed.
  • Move the mobile device closer to this device, at least until the connection is established.
  • Restart your mobile device, and unplug then re-plug in this device. We have observed cases where some mobile devices will fail to connect until it is restarted. This may happen more often after resolving a pairing issue or repeating the pairing process.
  • iOS Users: If the pairing process keeps failing, there may be a previous pairing that is no longer valid. Go into your device’s ‘Settings’ app, go to the ‘Bluetooth’ section, tap on ‘Forget Device’ if the device is listed there, and then try the pairing process again.
  • Disconnect your mobile device from other BT or WiFi networks, such as your vehicle’s infotainment / navigation / audio system.
  • Ensure that you have the latest firmware on your device (“Tools & Info” -> “Update Firmware”), as we have released a few updates to boost wireless performance and reliability.

Troubleshooting General Issues

  • Device Lights are Dim or Not On: Ensure that the device is fully inserted into the OBD port, that the vehicle’s OBD port is undamaged, and that no fuses are removed or blown. It is normal for the lights to be somewhat dim when viewed in daylight, as this device is intentionally designed to limit how much it lights up the inside of the vehicle at night.
  • Device Doesn’t Wake Up After Sleep (if Engine Off for Several Minutes): This device should wake up immediately upon pressing a button, or within 30 seconds of an engine start (typically much less). Simply turning on the ignition power may not be enough, so please ensure that the engine is running. This performance can vary depending on the electrical and data systems of your vehicle, and you may find options in its mobile app that give you the ability to customize the wake up behavior to better suit your situation.
  • Device is Unresponsive: Ensure that power is present, as indicated by light activity when plugging it in. Cycle its power by unplugging it and then plugging it back in. On vehicles with abnormal electrical systems and/or low battery capacity (including race cars with minimal / light-weight batteries), it’s rare but plausible that starting the engine could drop voltage lower than typical and glitch this device into a temporary unresponsive state.
  • Device is Unable to Detect or Communicate With Vehicle: Ensure that power is present, as indicated by light activity when plugging it in. Ensure that the vehicle’s ignition is on or engine is running. Some vehicles will power down its modules if the ignition power is left on for a period of time without the engine running, causing them to not communicate with this device. Ensure that the OBD port and related wiring is in good condition, there are no blown fuses, etc. Ensure that the vehicle supports OBD-over-CAN communications via the OBD port (nearly all 2009+ US market vehicles, and certain others before that). See more information in the Supported Vehicles section.
  • Missing Occasional Packets from CAN Sniffers or Traffic Monitors: First, ensure that the device is properly connected, and that the CAN module you are interested in is actually active and sending the data that you seem to be missing. Once those more likely causes are ruled out, there may be a small possibility of packet loss in extreme load situations. Although this device has been optimized for performance and tested with congested networks, its CAN sniffing capabilities are tailored towards providing an easy and affordable solution, and are not intended to compare to expensive laboratory equipment. You may be able to improve the situation by reducing the host CAN traffic and/or bus rate, temporarily turning data acceleration off (“DD ACCEL T 0”), and by sending a reset command (“AT D”, “AT Z”, “AT WS”, or “DD WD”) to clear out any temporary settings that may impact performance.

Troubleshooting use with 3rd Party Apps

  • See the supported app list for app-specific information and tips
  • You will need to have first used the official Dauntless OBD app to pair your phone with the device before it will accept communications from apps
  • Ensure that the app you are using supports either DauntlessOBD or ELM327-compatible devices over LE wireless communications
  • You may need to navigate the app’s options to set the wireless mode to “LE” / “Low Energy” or similar, and the device protocol to “ELM” or “ELM327”
  • You may also need to select your DauntlessOBD device from a list of paired or nearby devices
  • Contact the app developer for help

Troubleshooting Tips

  • Some vehicle OBD ports can be a bit tight and take extra effort to get it fully inserted; these also warrant some extra care where unplugging the connector from the port.
  • Other vehicles, or worn or damaged OBD connectors, can be loose and have a poor or intermittent connection. An OBD extension or “port saver” may be a way to get more useful life out of these.
  • If you were experiencing issues while connected via an OBD splitter or extension cable, try removing that and connecting directly to the vehicle’s OBD port to see if that resolves the issue.

Other Notices

This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions: (1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation.